Community antenna television (“CATV”) networks have been used for more then four decades to deliver television programming to a large number of subscribers. Increasingly, CATV networks are used by providers to provide data services to subscribers. For example, cable modems used in a broadband cable modem termination system (“CMTS”) compete with digital subscriber lines (“DSL”) and DSL modems used therein, which are typically implemented and supported by telephone companies. DSL service is typically provided over the same wires as a residence's telephone service.
Cable modems, on the other hand, use the CATV cabling over which CATV programming is provided. Some cable television and cable data providers compete with telephone companies by offering telephony services over the CATV network using Internet protocol. This is known in the art as ‘voice over IP’ (“VoIP”).
Conventional telephony networks provide electrical current from a central location to a user's telephony equipment for dial tone and off-hook signaling, for example. The power supplied from the telephone company's central location is provided from a utility company's power lines at the central office location under normal conditions, and is typically supplemented by a diesel generator in case off site power from the power company is interrupted. Thus, power for telephony service is always available; in an emergency, the local 911 operator can always be reached.
Although a CATV network often supplies some AC power for network devices, a subscriber's device or devices are typically powered by household AC current. Since most consumers do not have a diesel generator to back up off-site power supplied by a local utility company, batteries are typically used to provide a backup in case off-site power is lost. This allows a VoIP-over-CATV subscriber to place a telephone call during a power outage, including placing a call to a 911 operator in case an emergency situation requires contacting police, fire, paramedic, or medical personnel.
To increase reliability and reduce physical size, cable modem and other devices that support VoIP-over-CATV do not use the standard dry-cell batteries widely known to consumers in the familiar AAA, AA, C, D and 9-volt configurations. This is because rechargeable batteries are used so that immediately following a power outage, reasonable assurances are provided that the batteries will be operative. While power is being supplied from an off-site utility company, charge on the back-up batteries is being maintained or recharged. However, to maintain quality control and to facilitate particular size and shapes of devices, proprietary battery packs, preferably lithium ion, are provided by equipment manufactures to cable operators.
Although CATV equipment manufacturers typically try to design their products to be better than their competitors, a winning business strategy is based on the premise that the customer is always right and the customer comes first, as it is in other industries. Since cable operators, which are the customers of equipment manufacturers, typically stock these batteries and provide them to technicians who make service calls for equipment installation and/or maintenance, and provide batteries to customers who request replacement batteries, it is desirable to stock as few different types and styles of batteries as possible.
Accordingly, cable operators, who often incorporate equipment from more than one manufacturer, have requested that industry manufacturers agree to a design for battery cartridges that is interchangeable across a variety of devices from a variety of manufacturers. Thus, an operator would only have to stock a single type of battery. This would be advantageous because storing multiple batteries for multiple devices, among other things, requires more storage space, may result in the likelihood that certain batteries for products that are not widely used will loose the ability to retain charge after long storage periods and result in an increased likelihood that the wrong battery type may be provided for a given product.
Obviously, when different manufacturers market similar products, or similar particular aspects of competing products, they will seek to distinguish these competing products from one another. Thus, there is a need in the art to distinguish aspects related to the interchangeable battery, and its related device interface, among manufacturers. In addition to distinguishing the battery-related aspects among manufacturers, it is also desirable to provide a mechanism that facilitates installation and removal of a battery cartridge from a device.